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  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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  <script>
    /* // 1.声明一个年龄变量
    let age

    // 2.赋值
    age = 18
    // 把右边赋值给左边
    console.log(age);
     */

    //  let age = 18

    let num = 20
    let uname = '张三'
    console.log(num)
    console.log(uname)
    
  </script>
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